Hi, Unfortunately, I had no big success with playing with Google's OAuth Scopes.
But I found another solution ... Gmail-Account > Data & Privacy > Apps and services > Third party apps and services > Akonadi Service For Google Services ... I was able to send emails again via KMail. [ INFO ] Akonadi Resources for Google Services has some access to your Google Account To use some Akonadi Resources for Google Services features, you gave Akonadi Resources for Google Services some access to your Google Account. This access might include sensitive info [ See your profile info ] See your primary Google Account email address Associate you with your personal info on Google [ Read, compose, send, and permanently delete all your email from Gmail ] <--- so-called "Scopes" This app wants permission to do anything you can do in your Gmail, including: Read your emails Compose new emails Add new emails meant for a different email address into your inbox Send emails for you Delete your email Create, change or delete your email labels Get notified when certain kinds of emails appear in your Gmail inbox, like a travel confirmation Your email may contain sensitive info, like names of your contacts, your private communications, or financial or medical information [ CONCLUSION ] Unsure, if this was a clever/smart decision? BR, -Sedat-